1. Field of the Invention
The present invention relates to a reaction liquid, a set of an ink and the reaction liquid, and an ink jet recording apparatus and an image recording method using the reaction liquid. Particularly, the present invention relates to a reaction liquid used when performing recording on a recording medium using the reaction liquid and an ink in combination, a set of an ink and the reaction liquid, and an ink jet recording apparatus and an image recording method using the reaction liquid.
2. Description of the Related Art
As ink jet recording methods, various methods of recording images are proposed in which apart from a common ink for ink jet recording, a liquid for improving image quality is applied to a recording medium, prior to the application of the ink. For example, a method is proposed in which a liquid having a basic polymer is applied to a recording medium, and then, recording is performed with an ink containing an anionic dye (see Japanese Patent Application Laid-Open No. S63-060783). Also, a recording method is proposed in which a first liquid containing a reactive chemical species and a liquid containing a compound reactive with the reactive chemical species are mixed on a recording medium (see Japanese Patent Application Laid-Open No. S63-022681). Also, a method is proposed in which a liquid containing an organic compound having two or more cationic groups per molecule is applied to a recording medium, and then, recording is performed with an ink containing an anionic dye (see Japanese Patent Application Laid-Open No. S63-299971). Also, a method is proposed in which an acid liquid containing succinic acid and the like is applied to a recording medium, and then, recording is performed with an ink containing an anionic dye (see Japanese Patent Application Laid-Open No. S64-009279). Also, a method is proposed in which a liquid insolubilizing a dye is applied to a recording medium prior to the application of an ink (see Japanese Patent Application Laid-Open No. S64-063185).
Any of the above-described methods intend to suppress the blurring of an image and improve the water resistance of the image by precipitating a dye on a recording medium. However, in those methods, the effect of suppressing bleeding between a plurality of color inks is insufficient, and also, the precipitated dye is easily made nonuniformly distributed on the recording medium, so that the uniformity of image quality may decrease. Particularly, when plain paper or the like is used as the recording medium, this tendency may become remarkable because the precipitated dye only has low properties of covering the pulp fiber.
On the other hand, for a case where a pigment is used as the coloring material of the ink, an ink set in which an ink containing a pigment dispersion and another ink containing a polyvalent metal are used in combination for alleviating blurring in a multicolor recorded material is proposed (see Japanese Patent Application Laid-Open No. H09-118850). However, in this case, there is such a constraint for the ink containing a polyvalent metal that a polyvalent metal should be selected and used having regard to the compatibility between the polyvalent metal and the coloring material, in other words, the stability of the ink, so that sufficient image density may not be obtained, which is another problem.
Various methods that solve these problems and intend to achieve image uniformity and an improvement in image density are proposed. Specifically, recording methods in which a liquid composition containing polyvalent metal ions is previously applied to a recording medium, and then, an ink reactive with the liquid composition is applied for recording are proposed (see Japanese Patent Application Laid-Open No. S63-299970, Japanese Patent Publication No. H06-086142, Japanese Patent Application Laid-Open No. H09-207424, Japanese Patent Application Laid-Open No. H11-349873 and Japanese Patent Application Laid-Open No. 2000-094825). However, with any of these methods, high image density that satisfies demands for higher image quality in recent years may not be achieved, and image qualities obtained at the initial stage and after a lapse of time may become different.
Also, there is another problem that the recording medium to which the ink is applied causes the so-called curling, for example, curving or rolling due to water or a water-soluble organic solvent contained in the ink. As methods for suppressing this curling, several methods have conventionally been proposed. For example, an ink for ink jet recording containing a solid substance having four or more hydroxyl groups in the molecular structure and being soluble in water or an aqueous organic solvent is proposed (see Japanese Patent Application Laid-Open No. H04-332775). Also, as a curl-preventing agent, an ink containing saccharides, sugar alcohols, and a specific amide compound is proposed (see Japanese Patent Application Laid-Open No. H06-157955). Also, an ink containing specific polyalcohol and glycerin in combination is proposed (see Japanese Patent Application Laid-Open No. H10-130550). Also, an ink containing a solvent, a polymer binder, a mordant, a water-soluble curl preventing compound, a water-soluble desizing compound, a light resistant compound, an antifoaming agent and the like is proposed (see Japanese Patent Application Laid-Open No. 2000-019826).
As a result of the examination of the present inventors, it has become clear that a wet feeling of the surface of the recording medium (hereinafter referred to as “damp feeling”) due to insufficient evaporation of the components of the reaction liquid on the recording medium and insufficient fixability of the reaction liquid occurs, so that the texture of the recorded material may be impaired. Also, it has become clear that a curling of the recording medium is due to the water or the water-soluble organic solvent contained in the reaction liquid. Further, it has also been found that with any of the conventional techniques as mentioned above, the occurrence of this damp feeling cannot be suppressed, and the texture of the recorded material deteriorates. Further, it has also been found that, for example, when the reaction liquid is applied to the entire surface of the recording medium by a coating roller or the like, a damp feeling occurs more remarkably also in a portion where the ink is not applied (a paper white portion).
Also, according to the examination of the present inventors, it has been found that when the content of the surfactant in the reaction liquid is increased to improve the penetrability of the reaction liquid in contact with the ink, both in a liquid state, into the recording medium, blurring of the recorded image, that is, feathering occurs easily in the recorded image.
Further, for the reaction liquid, it is also important that no precipitates are produced even when the components in the reaction liquid and the like evaporate. When the reaction liquid is applied to the recording medium by an ink jet system, it is important that the production of precipitates is suppressed also for suppressing clogging in the nozzles of the recording head. Also, when the reaction liquid is applied to the recording medium by a coating roller, it is important that the production of precipitates is suppressed also for preventing the precipitates from scratching the surface of the roller and for reducing motor load applied, for example, when the roller is operated again after recording pause.